Hydraulic torque converters are known to be provided and utilized as a rotary torque communicating linkage between the rotary power output of an engine and the rotary power input of the engine's transmission. Such torque converters commonly comprise a rotatable hollow case which defines an interior power transfer space. Typically, such space is toroidal and is filled with pressurized hydraulic fluid. The case component of such converters is typically rigidly mounted to an engine's power output shaft or flywheel for 1:1 co-rotation of the case with the engine's crankshaft.
A radial array of impeller blades or vanes is commonly rigidly mounted to the case within the case's toroidal interior fluid filled space, such blades co-rotating with both the case and the engine's rotary output.
A turbine is typically rotatably mounted within the case, the turbine having an array of consistently pitched or angled blades or vanes which face the impeller blades. The turbine's rotary power output commonly comprises a transmission input shaft which emerges from the case through an axially aligned power output port. The annular seam or annulus between the turbine's output shaft and the inner periphery of such port is typically hermetically sealed for retention of pressurized fluid within the case.
In operation of such torque converters, engine power directly rotates the case and its co-rotating impeller blades. Fluid driven by the impeller blades impinges against turbine blades which are positioned immediately downstream from the impeller, such impingement rotating the turbine. The resultant turbine rotation rotates the turbine's power output shaft or socket linkage with a transmission's power input shaft. A mechanical linkage of the turbine to the transmission's rotary power input advantageously allows rotary torque from the engine to translate to the transmission exclusively hydro-dynamically via the pressurized fluid encased within the torque converter.
While such common hydraulic torque converters beneficially and advantageously allow for a very large differential between the rotational speeds of the impeller/case and the turbine during engine powered acceleration, such torque converters disadvantageously and undesirably assure that the turbine will not reach 100% of the rotation speed of the impeller/case. Such rotational differential results in mechanical inefficiencies during cruising operation of the engine and transmission.
To minimize such mechanical inefficiencies, fluid pressure actuated rotary clutches are known to be introduced into hydraulic torque converters, such clutches being selectively actuatable to provide a frictional 1:1 rotation linkage between the case/impeller and the turbine. However, such known fluid pressure actuated clutches typically undesirably require incorporation and installation additional complicated and expensive equipment. Such equipment may, for example, be adapted to transmit pressurized hydraulic fluid from the transmission into the torque converter for selective actuation of an interior hydraulic clutch. Such known clutch actuation assemblies often additionally require expensive rotation speed sensing and valve actuation equipment for actuating and de-actuating the hydraulic clutch at appropriate turbine rotational speeds.
In such known torque converter clutch assemblies, the ambient fluid pressure within the torque converter's toroidal interior space is typically utilized as the motive force for the stroke of a clutch actuating hydraulic piston (such stroke being either clutch engaging or clutch disengaging motion). Also, in such known assemblies, the motive force for oppositely driving or drawing the counter-stroke of such piston similarly constitutes fluid pressure pumped into or aspirated from a void at the opposite side of the clutch piston. The instant inventive hydraulic torque converter solves or ameliorates the above discussed hydraulic torque converter problems and difficulties by eliminating such fluid pumping and counter-stroke impelling equipment and structures, and by replacing such equipment with rollers and other specialized structures which enable the rollers to impel a clutch engaging piston counter-stroke, without any requirement of pumping fluids into or out the space underlying the piston.